Humidity controlling enclosure



March 17, 1970 HERNANPEZ ETAL 3,500,554

HUMIDITY CONTROLLING ENCLOSURE Filed April 10, 1968 3 Sheets-Sheet 1Fig./

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Tomas Hernandez Valenfin E. Lorenzo INVENTORS 9 0 BY m Auamq:

March 17, 1970 Filed April 10. 1968 Fig.4

T. HERNANDEZ ET AL HUMIDITY CONTROLLING ENCLOSURE 3 Sheets-Sheet 2 TomasHernandez Valentin E. Lanswza 1 N VEN TOR-5- March 17, 1.970 I HERNANDEZ3,500,554

. HUMIDITY CONTROLLING ENCLOSURE Filed April 10. 19.68 3 Sheets-Sheet sDUST COLLECTOR 76 UNIT PACKAGER F0R GRANULATES- OSCILLATING GRANU LATORTA 81. E T 54 k un ......-nd lug! Tomas Hernandez Va/enfln E. Lorenzo 8;IN VENTORS 0 w 9 M ED BY :22 WW EM L United States Patent 3,500,554HUMIDITY CONTROLLING ENCLOSURE Tomas Hernandez, 9220 SW. 38th St.,Miami, Fla. 33165, and Valentin E. Lorenzo, 119 NE. 20th St., Miami,Fla. 33137 Filed Apr. 10, 1968, Ser. No. 720,259 Int. Cl. F26b 17/00,21/06 U.S. CI. 34-51 4 Claims ABSTRACT OF THE DISCLOSURE A humiditycontrolling apparatus for substantially reducing water contamination ofhygroscopic materials of the type being processed by material processingmachines. The humidity controlling apparatus includes enclosure meansfor enclosing the portions of the material processing means in which thematerial being processed is handled and air pump means for pumpingheated air of low relative humidity into the enclosed portions of thematerial processing means in a manner such that the heated air withinthe enclosed portions of the processing means is maintained at apressure at least slightly above the pressure of the ambient atmosphere.

When medicinal tablets are formed, they are prepared from a medicinalsubstance and a diluent usually consisting of dextrose or a mixture oflactose and powdered sucrose in varying proportions. In many instances amoistening agent, such as a diluent alcohol, is also used. In theseinstances the greater the solubility of the medicinal substance inwater, the greater must be the percentage of alcohol in the excipient.However, where the active ingredients of such tablets may be decomposedby water or alcohol, other suitable binders and moistening agents areemployed. Most tablets which are compressed include an activeingredient, a diluent, a binder, a disintegrater, and a lubricant.Diluents are added when the quantity of active ingredient is small ordifiicult to compress. Binders give adhesiveness to the powder duringthe preliminary granulation and to the compressed tablet. Adisintegrating agent such as starch serves to assist in thefragmentation of the tablet after administration. Lubricants reducefriction between the tablet and the wall of the die during compressionand ejection cycles. In addition, they aid in preventing adherence oftablet material to the dies and punches.

It may therefore be understood that when forming some types of tabletsincluding active ingredients which may be decomposed by water, it isdesirable to reduce the possibility of these materials being subjectedto high humidity conditions. In addition, when tablets arebeingconstructed of hygroscopi materials, it is also desirable to limittheir contact with high humidity air.

While drying ovens have heretofore been utilized to pre-dry materials ofcompounds which are to be compressed into tablets so as to reduce thepossibility of humidifying hygroscopic materials and the decomposing ofother materials, such dried materials may be appreciably humidified orallowed to at least partially decompose by their being subjected to highhumidity air after they are removed from drying ovens or chambers priorto being submitted to other phases of manufacturing, including packagingprocesses. Accordingly, it is the main object of this invention toprovide a means whereby the materials or compounds being handled will bemaintained in a heated atmosphere of low relative humidity from the timethese materials and compounds are taken from drying ovens or chambersuntil they are packaged, either in loose granular form or in tabletform.

Another object of this invention is to provide a means wherebyconventional material processing machines of the type utilized inproducing tablets may be readily converted inaccordance with thepreceding object.

A final object of this invention to be specifically enumerated herein isto provide an apparatus in accordance with the preceding objects whichwill form to conventional forms of manufacture, be of simpleconstruction and easy to use so as to provide a device that will beeconomically feasible, long .lasting and relatively trouble free inoperation.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a fragmentary side elevational view of a tablet press withthe portion of the tablet press actually handling material of which thetablets are to be formed enclosed within a relatively airtight enclosurehaving heated air pump means operatively associated therewith;

FIGURE 2 is a front elevational view of the assemblage illustrated inFIGURE 1 as seen from the right side thereof;

FIGURE 3 is a top plan view of the assemblage illustrated in FIGURE 1;

FIGURE 4 is a vertical sectional view taken substantially upon a planeindicated upon the section line 44 of FIGURE 2;

FIGURE 5 is an enlarged vertical sectional view taken substantially upona plane indicated by the section line 5-5 of FIGURE 1; and

FIGURE 6 is a somewhat schematic overall perspective view of variousmaterial handling apparatuses utilized in the forming of medicinaltablets and powders and the packaging of the tablets and powders withthe humidity controlling structures of the instant invention relativelyassociated therewith.

Referring now more specifically to the drawings, the numeral 10generally designates a drying oven, the numeral 12 an oscillatinggranulator, the numeral 14 a mixer including a tiltable hopper 16, thenumeral 18 a unit packager for granulates and powders, the numeral 20 atablet press, the numeral 22 a tablet duster, the numeral 24 a unitpacker for tablets, and the numeral 26 a dust collector, see FIGURE 6.

The drying oven 10 may be of any conventional design includingvertically spaced and suitably driven endless conveyors 28, 30, 32, 34and 36, an inlet funnel 38 opening upwardly through the top of the oven10 above the upper conveyor 28 and an outlet funnel 40 disposed belowthe outlet end of the lower conveyor 36 and opening downwardly throughthe bottom wall of the oven 10.

The oven 10 may be heated by any suitable means (not shown) and theendless conveyors may be powered by any suitable power source (notshown).

The oscillating granulator is conventional in design and includes anupwardly opening hopper 42 and the mixer 14 as well as the unit packager18 are also conventional in design. Further, the tablet press 20, thetablet duster 22, the unit packager for tablet 24 and the dust collector26 are also of conventional design although these various machines havebeen modified in order to enclose the portions thereof, except for thedust collector 26, which handle the material being processed.

The granulator 12 has been provided with a removable closure cover 44for its hopper 42, the mixer 14 has been provided with a removableclosure cover 46 for its hopper or receptacle 16, the unit packager 18has been provided with a closure cover 48 for its inlet funnel 50, thetablet press 20 has been provided with an enclosure referred to ingeneral by the reference numeral 52 for the component of the press 20which actually process the material to be pressed into tablet, thetablet duster has been provided with a removable closure cover 54 andthe upper portion of the unit packer has been provided with a removablecover 55. In addition, the inlet funnel 38 of the oven has been providedwith a sliding closure door 56 and the outlet funnel 40 of the dryingoven 10 has been provided with a sliding closure door 58. The outletfunnel 40 and the closure cover 44 include outlet and inlet neckportions 60 and 62 with which the inlet and outlet ends, respectively,of a conduit 64 are communicated. Further, the lower portion of thehopper 42 of the granulator 12 includes an inlet neck 66 and an outletneck 68 while the closure cover 46 for the mixer 14 includes an inletneck 70, the inlet and outlet ends of a conduit 72 being communicatedwith the outlet neck 68 and inlet neck 70, respectively. Further, theclosure cover 46 includes an air outlet tube 74 provided witha'removable closure 76 on its outlet end. The closure cover 48 for theinlet funnel 50 of the unit package 18 includes an inlet neck 78 towhich the end of the conduit 72 remote from the mixer 14 may beconnected in lieu of being connected to the outlet neck 68. Further, theend of the conduit 72 remote from the mixer 14 may also be connected toan inlet neck 80 opening through the hinged closure 82 of the enclosure52.

The enclosure 52 defines an outlet neck (not shown) to which one end ofa conduit 84 is connected and the other end of the conduit '84 opensinto the closure cover 54. The end of the closure cover 54 remote fromthe conduit 84 defines an outlet funnel or neck 86 to which one end of aconduit 88 is connected. The closure cover 55 includes an inlet neck 90to which the end of the conduit 88 remote from the funnel 86 isconnected and the heated and dried air outlet conduit 92 extending froma controllable heater and blower assembly referred to in general by thereference numeral 94 also opens into the top of the closure cover 55.Further, the enclosure 52 also defines an outlet opening (not shown) towhich the inlet end of a conduit 96 is connected and the outlet end ofthe conduit 96 opens into the vacuum producing dust collector 26 as at98. The tablet duster may be conventional in design and thereforeincludes its own vacuum pump (not shown) which may or may not beactuated, as desired. Also, an air heating and pumping assemblygenerally referred to by the reference numeral 100 is provided andincludes an outlet conduit 102 which is connected to the inlet neck 66of the receptacle or hopper portion 42 of the oscillating granulator 12.

With attention now invited more specifically to FIG- URES 1-5 of, thedrawings, it may be seen that the enclosure 52 defines a housingincluding front and rear walls 104 and 106 interconnected by means ofupstanding opposite side walls 108 and 110 as well as top and bottomwalls 112 and 114. The top and bottom walls 112 and -114 as well as thefront and rear walls 104 and 106 have upper, lower and intermediatemounting block portions 116, 118, and 120 secured thereto and theopposite side walls 108 and 110 are removably secured to the mountingblock portions 116, 118 and 120 by means of releasable fasteners 4 122.The opposite side walls 108 and each include upper and lower pairs ofchannel defining members 124 from which sliding closure panels 126 aresupported and each of the closure panels 126 is shiftable into and outof positions closing a corresponding opening 128 formed through thecorresponding side wall.

The rear wall 106 is cut away as at 130 to closely embrace the portionsof the tablet press 20 extending therethrough and the bottom wall 114 isalso cut away as at 132 to closely embrace the portions of the tabletpress 20 extending therethrough. Accordingly, the hopper portion 134 asWell as other portions of the tablet press 20 which actually handle thematerial to be pressed into tablets are completely enclosed within thehousing or enclosure 52 and the rear wall 106 of the housing 52 includesan inlet opening 136 to which the outlet end of a heated and dried airconduit 138 is connected. The heated and dried air conduit 138 includesan inlet end connected to the discharge nozzle 140 of an air heating andpumping assembly referred to in general by the reference numeral 142.

, The front wall 104 of the enclosure 52 has a hygrometer generallyreferred to by the reference numeral 144 secured therethrough and athermometer 146 is supported inwardly of and from the front wall 104 bymeans of mounting blocks 148. Still further, the top wall 112 includes ahinged closure or cover 82 upwardly through which the inlet neck 80 issecured when the latter is utilized.

When only the basic concept of the invention is practiced, the enclosure52 as illustrated in FIGURES 1-5 is utilized on the tablet press 20. Thehinged closure cover 82 may be opened so as to provide access to thehopper or inlet funnel 134 of the tablet press 20' and the material tobe pressed into the tablet may be discharged downwardly into the hopper134. However, the interior of the enclosure '52, has already been heatedby a supply of heated dry air from the air heating and pump assembly142- Any of the closure panels or doors 126 may be left slightly ajar,or closed as desired, to provide the desired increased air pressurewithin the enclosure 52 and as soon as the temperature within theenclosure 52 has been raised to the desired point as indicated by thethermometer 146 and the hygrometer reading has dropped sufficiently, thematerial to be processed by the tablet press may be placed into thehopper 134 for pressing into tablets. The enclosure 52 thereby maintainsa heated dry atmosphere about the portions of the press 20 which handlethematerial to be pressed into tablets and the heated atmosphere ismaintained at pressure at least slightly greater than the pressure ofthe ambient air in order that any leaks between the enclosure 52 and thetablet press 20 will have heated dry air flowing outwardly therethroughas opposed to cooler humid air flowing inwardly therethrough into theinterior of the enclosure 52 for water contamination of hygroscopicmaterials being handled by the tablet press 20 or deterioration of othermaterials being handled by the press.

When installed, the enclosure 52 is substantially permanently mountedand access to the portions of the tablet press 20 disposed interiorly ofthe enclosure 52 may be gained through the openings 128. Further, thevarious wall portions of the enclosure 52 are constructed of transparentmaterial and therefore the complete normally exposed operation of thetablet press may be observed through the wall portions of the tabletpress 20.

When only the enclosure 52 is to be utilized in conjunction, with theair heating and pumping assembly 142, the closure cover 82 may beprovided without the inlet neck '80 or if the inlet 80 is provided itmay be suitably capped so as to prevent excessive loss of air pressurewithin the enclosure 52.

However, when the invention is practiced to the extent illustrated inFIGURE 6, the enclosure 52 not only includes the inlet neck 80' but isutilized in conjunction with other air heating and pumping assembliessuch as the assemblies 94 and 100. While the air heating and pumpingassembly 142 may also be utilized, its use is not necessary and theinlet end of the conduit 96 may be secured in the opening 136 in lieu ofthe outlet end of the conduit 138. On the other hand, if the heating andpumping assembly 142 is provided, the rear wall 106 of the enclosure 52is provided with an additional opening similar to opening 136 in whichthe inlet end of the conduit 96 is secured.

The various closure covers 44, 46, 48, and 55, together with theenclosure 52 and the various conduits 64, 72, 84, and 88, completelyenclose all of the components utilized to process the material which isbeing handled. The material to be processed is first placed into thefunnel 38 of the drying oven after the heating means (not shown) of thedrying oven 10 has been actuated. The assemblies 94 and 100 may beactuated in order to purge all of the enclosures with heated dry airalthough it is not .necessary to actuate the assembly 94 until such timeas the first batch of material is to be delivered to the tablet press20.

The closure door 56 of the drying oven 10 may be opened in order thatthe material fed into the inlet funnel 38 may fall down upon and behandled by the various inlet conveyors 28, 30, 32 and 34 during themovement of the material through the drying oven 10 before its dischargetherefrom through the outlet funnel 40 after the closure door 58 hasbeen opened. However, the assembly 100 is operated to pump heated airthrough the conduit 102, into the hopper 42, through the conduit 64 andinto the oven 10. The material discharged from the oven 10 flows throughthe conduit 64 into the hopper 42, the latter being disposed at a lowerelevation than the drying oven 10, and after the desired batch ofmaterial has been received in the hopper 42, the oscillating granulatormay be actuated to regranulate the material therein. As the material isregranulated in the oscillating granulator 12, it is dischargedtherefrom through the conduit 72 into the hopper 16 of the mixer 14, thehopper 16 also being at a lower elevation than the hopper 42.Thereafter, the removable cover 76 is removed and the previously driedlubricant may be added to the hopper 16 for mixing with the driedmaterial. The operation of the assembly 100 may then be terminated andthe cover 76 may be reapplied to the tube 74 after which the mixer maybe actuated until the contents of the hopper 16 have been thoroughlymixed. Thereafter, the hopper 16 may be tilted so that the mixedmaterial therein may flow outwardly through the conduit 72, the end ofthe conduit 72 previously connected to the outlet neck 68 beingconnected to either the inlet neck 78 or the inlet neck 80, as desired.Of course, if the conduit 72 is connected to the inlet neck 78, thematerial processed in the granulator 12 and mixed in the mixer 14 isthen processed by the packager 18 for packaging in individual packages.On the other hand, if the conduit 72 is connected to the inlet neck 80,the material discharged from the mixer as the hopper or reservoir 16 'isslowly tilted is discharged into the hopper or inlet funnel 134 of thetablet press 20 and the latter acts to form tablets out of the materialsupplied thereto. The air heating and pump assembly 94 is of courseactuated before the tablet press 20 is put into operation in order thatthe interior of the enclosure 52 may be purged with heated dry air. Ofcourse, the interiors of the closure covers 54 and 55 will also bepurged with heated dry air. Further, the dust collector includes vacuumpump means (not shown) whereby air from within the enclosure 52 ispumped therefrom thereby ensuring a continuous flow of heated air fromthe assembly 94 through the closure covers 54 and 55 and the enclosure52.

As tablets are discharged downwardly from the tablet press 20, they passthrough the conduit 84 into the tablet duster 22 in which the brokenpieces of tablets and dust are removed. Then, the dusted tablets aredischarged from the duster 22 into the conduit 88 and are cbnveyedthrough the latter into the closure cover 55 of the unit packer 24.

From the foregoing, it may be seen that the various material handlingmachines illustrated in FIGURE -6- are each enclosed in a manner suchthat they may be read ily provided with heated dry air thus preventingthe material being handled from contamination by moisture and preventingmaterials which deteriorate when subject to high humidity conditionsfrom deteriorating.

As hereinbefore set forth, each of the various material handlingmachines may have an air heating and pump assembly such as the assembly142 operatively connected thereto in order that each machine will havethe working portions thereof disposed in a heated dry atmosphere. On theother hand, the assemblies and 94 together with the various conduitsconnecting the material handling machines may be used in conjunctionwith or in lieu of the assembly 142 in order to maintain the materialsbeing handled by the machines illustrated in FIGURE 6 completely free ofhumid air from the time the materials are placed in the drying oven 10until they are discharged from the unit packager 18 or the unit packer24.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. In combination with a machine having components thereof for handlinghygroscopic materials, a cover assembly for said machine therefrom andenclosing at least said components of said machine, means operative topump heated air of low relative humidity into said cover assembly and tomaintain the atmosphere within said cover assembly at a pressure atleast slightly above the pressure of the ambient atmosphere, saidmachine including an upwardly opening hopper in which material to behandled by said machine are downwardly receivable, said hoppercomprising one of said components and said cover assembly including atop wall portion overlying said hopper and having an inlet openingtherein in registry with said hopper through which material may bepoured into said hopper from thereabove, said cover assembly including acover member movable into and out of position closing said inlet openingand wall portions having access openings formed therein through whichmanual access to said components may be gained from the exterior of saidcover assembly as Well as closure members movable into and out ofpositions closing said access openings, said cover assembly alsoincluding wall portions thereof constructed of transparent material andthermometer means readable from the exterior of said cover assembly andoperative to indicate the temperature of the atmosphere in said coverassembly as well as hygrometer means also readable from the exterior ofsaid cover assembly and operable to indicate the humidity of theatmosphere in said cover assembly.

2. In combination with a pair of machines having components thereof forhandling hygroscopic materials, said machines including material inletand outlet means operative to receive and discharge material to behandled and one of said machines being adapted to first handle saidmaterial and conduit means communicating the outlet means of said onemachine with the inlet means of the other machine, and a cover assemblyfor each of said machines enclosing at least said components thereof andinto which the inlet means for said machines open, and means operativeto pump heated air of low relative humidity into the cover assembly ofsaid second machine for conveyance ofsaid heated air through saidconduit means and into the cover assembly of the first machine.

3. The combination of claim 2 wherein the cover assembly of said onemachine includes thermometer means readable from the exterior of saidcover assembly and operative to indicate the temperature of theatmosphere therein as well as hygrometer means also readable from theexterior of the cover assembly of said one machine and operative toindicate the humidity of the-atmosphere therein.

4. The combination of claim 2 wherein said cover assembly of said onemachine includes wall portions having access openings formed thereinthrough which manual access to said components of said one machine maybe References Cited UNITED STATES PATENTS 10/1895 Moller et al. 34181 X3/1939 Smith 34-51 10 LLOYD L. KING, Primary Examiner US. Cl. X.R. 34181

